Model activities, companies, friends, and rules

Activities are structured data parsed from raw text messages (1-to-1).
They are associated with companies (1-to-N), where each company is
associated with a friend (N-to-1).

Companies associate actiities with group of friends who participated in
each of them.

Friends are represented by names and fb_ids. Fb_ids are used to fetch
FB profile pictures.

Rules are manually created to parse raw text messages into structured
activities. New rules are added as needed when parsing new text
messages. Old rules are applied to new text messages, sometimes parisng
it all, other times parsing it just partially.

Each time new rules have to be written for a particular message, that
message and the new rules should be captured in Rspec.
Add spork and ffaker
Add nyan cat to command line rspec
Add activity commands

#set_name
#set_category
#set_accomplishment
#set_mood
#add_friend
#add_duration